I followed the instructions in the service manual for the pressure test, so these reading are all taken using the test port that is just a few inches forward of the shift linkage connection, on the drivers side.

 

What I would like to see is what the pressure is on the forward clutch pressure tap when you put it in drive. Same for the reverse port.

D

 

I'm completely mystified. Last night I poked around a bit and decided to get another read on the line pressure tap. First I notice, that in P, the pressure is now only about 60. I drop it in R and I feel it sync, drop in and load down the motor. WTF... I run it through the rest of the gears slowly... the pressures at idle are all ~2/3 of what I reported above (except N which stayed at ~40), but every single gear works perfectly and smoothly. I took the damn thing for a test drive around the area for about 10 minutes with no complaints... all the way up through OD.

The ONLY thing I did before starting it, was move the 4WD floor shift from 2H to 4L and back up to 2H. I can't see how that would matter (but that's why I'm here asking questions) From what I can tell in the service manual, the 4WD gear select sensor should only affect the shift points in the tranny, NOT whether it engages or not. ???

More test driving and leak checking to come, but it seems to be fixed (and it bothers me that I don't know why.) Must be magic.

Unless more magic ensues, I hope this is my last post on the subject. Thank you to all who contributed, especially Darrin who came with practical diagnostic steps. I wish this thread would benefit somebody, but unless they have a wand to wave, I'm not sure that it will, much.

Now to deal with the smoking exhaust issue. (which is also much less than originally <sigh>) Compression test to come this weekend, but that story doesn't belong here.